Status: Not Connected despite plugin can see Redis server

Kubernetes, using a custom docker image with debian buster PHP 7.3 fpm, Apache. Connecting to an in-cluster Redis cluster directly. No matter which version of php-redis i install (4.2.0 Debian Buster default, or, 5.2.2 latest or 5.1.0 version from PECL) i still get status Not Connected. The plugin can see the Redis server and ping it however, also can get its info. Using a sidecar im able to connect to the server and query it easily with redis-cli. The Redis cluster requires -c flag (allowing redirection of queries?) maybe that is the reason?